A major problem associated with double cone or ring crimping machines is the lack of sufficient clearance for loading large diameter fittings and bent fittings, particularly the latter. This problem is illustrated in FIGS. 1 and 2 wherein it can be seen that as die cones 1 retract to open dies 2, the inside edge 2 of the die cones projects radially inward into the opening through which a fitting is inserted to be crimped, thereby partially obstructing the opening. The restricted opening not only makes it difficult to insert larger diameter fittings, but also makes it particularly difficult, if not impossible, to insert many bent fittings. PCT Patent Application Ser. No. PCT/EP/00024, filed on Feb. 1, 1983, to Sauder discloses a double cone crimping machine of this general type.
FIG. 3 through 5 illustrate the crimping head components of another double cone crimping machine in use today which utilizes a pair of two-step cones 5 and a plurality of radially arranged two step dies 7. This crimper is finding acceptance because it requires less cylinder stroke than the crimper illustrated in Figures 1 and 2. However, it can be appreciated, from Figures 3-5, that each two-step cone is quite wide. This is because part of each cone (i.e., that part identified by dimension X) extends beyond edges 9 of die 5 when the components are in their open loading position. The extension of the cones beyond the die's edges is undesirable because it increases the overall length of the crimping assembly or head, thereby increasing the distance a fitting must be inserted between the dies. This not only makes it more difficult to insert a bent fitting through the dies, but also decreases the size of bent fittings which can be inserted into and through the dies.
A two step, double cone crimping machine which is similar to that illustrated in FIGS. 3 through 5 is Saudr Press Model No. Type 88 made by Saudr Press AG of Zurich, Switzerland. The axial length or distance a fitting can be inserted through this crimper is 8.25 inches and the radial distance travelled by one of the crimping die members during a stroke of the crimper is 0.645 inches. This provides the Saudr Type 88 crimper with a relatively high axial crimper length to radial die movement ratio of 12.8:1. As such, many of the larger bent fittings cannot be inserted through the crimper, at least not without first removing the die members from the crimper's crimping head which, quite obviously, is a time consuming task.
Another problem associated with double cone crimpers is the difficulty of setting or adjusting the axial position of the crimpers depth stop. The depth stop's position is adjusted to axially position the hose assembly so that the crimper's crimping members engage only the hose assembly's outer ferrule, thereby not crushing any portion of the hose fitting itself. Unfortunately, in double cone crimping machines the depth stop usually travels axially along the axis of the crimping machine at twice the speed of the crimping members. This happens because the crimping members ride on both the front and rear cones, thereby moving both axially forward and radially inward but only at half the forward axial speed of the hydraulic activating means. Accordingly, it is very difficult to adjust the depth stop so that the crimping members engage only the ferrule. Moreover, even if the depth stop is properly adjusted, it tends to continue to push the ferrule through the crimping members even after the crimping members being crimping the ferrule since the depth stop is still moving at twice the speed of the crimping members.
A method of solving this problem, involves the use of a take-up spring which compresses as the crimping members crimp the ferrule. This solves the depth stop pushing problem; however, it does not solve the more difficult problem of properly adjusting the axial position of the depth stop so that the crimping members engage only the ferrule at the instant crimping begins.
An object of the present invention is to provide a crimping apparatus having a crimping head which is capable of accommodating most standard bent fittings.
Yet another object of the present invention is to provide a double ring crimping apparatus which reduces the speed of the crimping apparatus' depth stop so that the axial position of a member to be crimped by the crimping apparatus can be maintained relative to the crimping members during the apparatus' crimping stroke.
These, as well as other objectives, will become apparent from a reading of this disclosure and claims and an inspection of the accompanying drawings appended hereto.